Estimating Crime Counts and Characteristics from NIBRS Data
摘要
Develop statistical methodology for computing estimates of crime rates and characteristics from National Incident-Based Reporting System (NIBRS) data that accounts for missing data, produces estimates that are consistent across population domains and levels of geography, and can be replicated or adapted by other researchers. Apply the methodology to estimate counts and characteristics of crimes for Arizona in 2021.
MethodsOffense counts are obtained for a probability sample of non-NIBRS-reporting agencies. NIBRS records are then imputed for each incident in the offense count for each sampled agency. Standard errors are calculated using the probability sampling design and variability from multiple imputations.
ResultsEstimates of Arizona violent and property crime rates from the probability sample are consistent with the Uniform Crime Reporting Program time series and are similar to estimates from the Arizona Department of Public Safety. Crime rate estimates that ignore the missing data, and estimates from “The Transition to the National Incident-Based Reporting System (NIBRS): A Comparison of 2020 and 2021 NIBRS Estimates” (Federal Bureau of Investigation
The methodology produces accurate estimates of crime rates with valid confidence intervals. Estimates of offense, victim, and offender characteristics are based on imputation models with openly stated assumptions. Future research could include a large-scale study to identify “optimal” imputation donor sets for non-NIBRS-reporting agencies.